Abstract The synthesis of 1, 2, 3, 4-tetrahydropyrazolo [4, 3-c][1] benzazepin-1-ones 1 and that of its 10-methyl derivative 2 is reported. The preparation of the latter from 3-(2- aminobenzyl) 3-pyrazolin-5-one and triethyl ortho-formate gave as the main product a derivative of the new tricyclic ring system, pyrazolo [1, 5-c][1, 3] benzo-diazepine. The structures of the new compounds synthesized were assigned by means of a 13 C nmr ...
